A continuous mining machine which is capable of mining ultra thin coal seams (having a thickness of around two feet or less) is described in U.S. Pat. No. 5,871,260 (the disclosure of which is hereby incorporated by reference herein). According to the present invention a conveyor cart is provided which may be advantageously used with the continuous miner of U.S. Pat. No. 5,871,260, and the invention also relates to a combination of the miner of U.S. Pat. No. 5,871,260 and a conveyor for effectively mining ultra thin coal seams and the like.
In order to effectively convey coal mined by the continuous miner of said co-pending application to the mine mouth the conveyor utilized with the miner should have a maximum height of about 20 inches or less. Also, in order to be cost effective, the conveyor should be constructed from as many off the shelf commercially available components as possible. Such a conveyor must also have high maneuverability and reliability, and must be easy to connect and disconnect from the mining machine, and from other conveyor components, so that a conveyance path of any desired length may be provided.
According to the present invention a conveyor cart is provided as the desired conveyor for use with the continuous miner of said co-pending application. The conveyor cart according to the invention is advantageously constructed from virtually all readily available, off the shelf, components, and is especially cost effective, and is made maneuverable, yet highly functional, by employing components typically used in conventional golf carts, such as the "Club Car".RTM. golf carts available from Club Car Inc. of Augusta, Ga., an Ingersoll-Rand company.
According to one aspect of the present invention, a conveyor cart for a mining machine (such as in said co-pending application) is provided comprising the following components: A chassis comprising first and second side rails, and a plurality of cross pieces extending between the side rails, each side rail having a first end and a second end. A first coupling mechanism mounted adjacent the first ends of the side rails for coupling the cart to a like cart. An axle extending generally perpendicular to the side rails and closer to the second ends of said side rails than the first ends. First and second wheels mounted to the axle on opposite ends thereof. An endless conveyor belt. Means for mounting the conveyor belt to the chassis so that the conveyor belt has a top portion for conveying mined material thereon, and a bottom portion, and so the top portion moves from adjacent the first ends of the side rails toward the second ends of the side rails while the bottom portion moves oppositely. Means for moving the conveyor belt with respect to the chassis so the top portion moves from the first ends of the side rails toward the second ends of said side rails while the bottom portion moves oppositely. And, a second coupling mechanism mounted adjacent the second ends of the rails and beneath the bottom portion of the conveyor and closer to the second ends of the rails than the wheels, for coupling the cart to a like cart, so that when two like carts are coupled together the top surface of the leading cart is above the top portion of the trailing cart.
The means for mounting the conveyor belt preferably comprises a first roller adjacent the first end of the side rails and extending substantially perpendicular thereto; a second roller adjacent the second end of the side rails and extending substantially perpendicular thereto; and top surfaces of the cross pieces disposed between the top and bottom portions of the conveyor belt and engaging a bottom surface of the top portion of the conveyor belt. One of the rollers is driven by the means for moving the conveyor belt, which preferably comprises a conventional, off the shelf, air cooled electric motor, such as a five horsepower TEFC electric motor available from Dodge and known by the trade name Gearmotor No. WG-28A. The conveyor cart has a maximum height of 20 inches or less, preferably about 18 inches.
The conveyor cart further comprises means mounted on the chassis for powering the axle and thereby driving the wheels. The means for powering the axle preferably comprises an air cooled AC motor and a golf cart transmission, both mounted adjacent the axle. The wheels are preferably inflatable golf cart tires, and the axle preferably comprises a golf cart axle. The means for mounting the conveyor belt further comprises directing rollers for causing the bottom portion of the belt to pass over the axle, motor, and transmission in moving from the second roller to the first roller. Also the conveyor cart preferably comprises an electrical wire mounted to the chassis and electrically connected to the A C motor, and having a female plug and a male plug, the female plug adjacent the first ends of the side rails, and the male plug adjacent the second ends of the side rails. Also the axle and the wheels preferably comprise the only axle and wheels of the cart, making the cart highly maneuverable and inexpensive.
The cart may further comprise an electrical cable supporting trough mounted to at least one of the side rails for mounting an electrical cable therein (which electrical cable powers the continuous miner), and a clamping mechanism would be mounted on the chassis for clamping a safety cable to the chassis (the safety cable being connected to the continuous miner and reel at the mine mouth). While the first and second clamping mechanisms may comprise any of a wide variety of conventional ball joints, universal joints, pintle hooks, or the like, preferably the first coupling mechanism comprises an eye bolt while the second coupling mechanism comprises a pintle hook, the coupling mechanisms allowing pivotal movement, about a substantially vertical axis, of a trailing cart with respect to a leading cart when coupled together.
According to another aspect of the present invention a conveyor cart for a mining machine is provided comprising: A chassis comprising first and second side rails, and a plurality of cross pieces extending between the side rails, each side rail having a first end and a second end. An axle extending generally perpendicular to the side rails and closer to the second ends of the side rails than the first ends. First and second wheels mounted to the axle on opposite ends thereof. An endless conveyor belt. Means for mounting the conveyor belt to the chassis so that the conveyor belt has a top portion for conveying mined material thereon, and a bottom portion, and so the top portion moves from adjacent the first ends of the side rails toward the second ends of the side rails while the bottom portion moves oppositely. Means for moving the conveyor belt with respect to the chassis so the top portion moves from the first ends of the side rails toward the second ends of the side rails while the bottom portion moves oppositely. And, wherein the cart has a maximum height of twenty inches [0.5 meters] or less. The details of the components of the cart may be as described above.
According to another aspect of the present invention a continuous mining machine system is provided. The system includes the continuous mining machine, as in U.S. Pat. No. 5,871,260 and a plurality of wheeled conveyor carts. The mining machine comprises the following components: a chassis supported by crawler tracks, and having a front and a rear and elongated in a first dimension between the front and the rear; a substantially horizontal axis powered cutter head mounted to the front of the chassis; a conveyor mounted to the chassis and including an endless conveyor chain; the chain connected to first and second sprockets, the first sprocket mounted for rotation about a first shaft adjacent the rear of the chassis, and the second sprocket mounted for rotation about a second shaft adjacent the front of the chassis but between the first sprocket and the cutter head; the first and second shafts rotatable about axes generally perpendicular to the first dimension; at least one motor for driving one of the first and second shafts to thereby drive one of the sprockets and the conveyor; a gathering head mounted adjacent the front of the chassis and below the cutter head and at least partly to the rear of the cutter head, for gathering material cut by the cutter head and moving the cut material to the conveyor, the gathering head comprises a pair of counter-rotating discs with upstanding vanes, and an angled deck substantially coplanar with the disc; the second shaft having first and second transmission elements connected thereto, the first and second transmission elements operatively connected to the discs for effecting counter-rotation driving thereof; the angled deck during normal operation making an angle with respect to the dimension of elongation of the chassis, the chassis having a maximum height of about twenty inches, and the cutter head having a maximum diameter of about twenty two inches.
The system further comprises a plurality of wheeled conveyor carts connected to the continuous mining machine, each cart having a self contained driven conveyor belt associated therewith, and a maximum height of twenty inches or less. The wheeled conveyor carts preferably are as described above, and preferably some but not all of the conveyor carts are powered (having means mounted on a chassis thereof for driving the cart wheels). That is approximately one out of every three of the conveyor carts may include means mounted on the chassis for driving the cart wheels. Typically each cart has a maximum width of less than six feet (the wheels being the maximum width portion thereof, and is between about 10-14 feet long (e.g. about 12 feet, or four meters, long). The system may further comprise a safety, retrieval, cable securely connected to the mining machine, the cable supported by the conveyor carts and connected to a take-up drum.
It is the primary object of the present invention to provide an effective conveyor cart for a continuous mining machine system, and a continuous mining machine system per se, especially for mining ultra thin coal seams or the like. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.